Drying-cylinder.



No. 695,04l. Patented Mar. Il, |902.

E. FuEs.

DRYING CYLINDER.

(Application led July 19, 15301,1l (No Model.)

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lPinTnNT ERNST FUES, OF I-IANAU, GERMANY.

DRYlNG-CYLINDER.

SPECIFICATION forming part of lLetters Patent Nc. 695,041, dated March 11, 190:2. Application filed Julyl, 1901. Serial No. 68.978. (No model.)

To @ZZ w/"t'om it may concern:

Be it known that I, ERNST FUES, a-subject of the Emperor of Germany, and a resident of Hanau, Germany, (whosepostal address is Dr.` Ernst Eues, Hanau, Germany,) have invented certain new and useful Improvements in Drying-Cylinders, of which the following is a specification. Y

The present invention relates to the heating of drying-cylinders used in the manufacture of paper and in other industries, such cylinders being heated indirectly by the employment of heat-transmitters and in such a manner as to rem o ve all danger of explosion. The said heat-transmitters are arranged in the interior of the drying-cylinder itself, between the actual heating-bodies--for instance, coils or spakes heated by steam--and the walls of the cylinder.

In the accompanying drawings, Figure l represents a longitudinal section of a drying- 4 cylinder, showing the use of a liquid heat transmitter or conductor surrounding the heating-coil between an outer and inner cylinder. Fig. 2 is a longitudinal section of a modification of my invention, in which the heating coil or pipe is formed by the corrugations between the outer and inner cylinders.

Steam at any suitable pressure inclosed in absolutely pressure-safe pipes or heating bodies is conducted backward and forward in and out of the two hollowjournals or trunnions A of the drying-cylinderB and through sinuous conduits C, arranged in the requisite number inside the latter near the walls of the cylinder. The heat of the steam is transmitted by the sinuous conduits or heatingpipes O to the heat transmitter or conductor D, already referred tc, and the latter conducts the heat uniformly to the Whole surface of the cylinder. Of course the front and end walls E F of the cylinder are so constructed and arranged with heat-insulating material that they radiate heat to the least possible extent.

Liquids-as, for instance, solutions, oils, molten metals, and metal alloys-*or solidsas, for instance, sand, broken glass, and metal iilings, graphite-powder, or the like-may be used as the heat-transmitter D.

The quantity ofthe heat-transmitter must,

on the one hand, be sufficient to insure the entirely uniform distribution ofthe heat over the whole of the cylindrical surface to be heated, and, on the other hand, the said quantity must not be above a certain limit, because it must be possible to rapidlyregulate the ternperature of the cylinder by opening and closing the steam-inlet valve. Both in the case of liquid and solid heat-transmitters the most suitable quantity is obtained by placing inside the main cylinder B another cylinder Gr, concentric with the former and of suitable dimensions.

For use with liquid heat-transmitters the heating-tubes C and the inner cylinder Gmay be made stationary, as represented in Fig. l. As there is no pressure inside the cylinder, as will be hereinafter explained, it is not difficultto make the joint between the rotating hollow journals a of the cylinder B and the stationary steam pipes or trunnions A, passing through the same, steam-tight. The rotation of the outer cylinder B around the heating-tubes C and the inner cylinderGproducesa whirling eddying motion ofthe liquid D in the annular space between the two cylinders B and G, and thus causes the said liquid to rapidly and uniformly transmit to the outer cylinder the heat received from the heating pipes. The intermediate heating liquids must possess the following characteristics, viz: a boiling-point which is higher than the temperature of the steam used, stability with regard to the temperatures occurring, and a chemically-neutral inactive attitude with regard to the metals with which it comes into contact. Owing to its combination of all the said characteristics, paraffin or paraffin-oil (boiling-point 350O to 400) is particularly suitable for the purpose.

It a solid is used as an intermediate heatconductor D, the heating passages or coils, as well as the inner cylinder G, must revolve with the outer cylinder B. Such a construction is shown in Fig. 2, where the heating passage or pipe C is in this case formed by the corrugations between the outer cylinder B and theinner corrugated cylinder G.` In this case steam-tight connections of the usual kind must be arranged between the stationary and revolving ends d e of the heating-pipes, both at the side at which steam enters and where IOO it leaves.. Instead of saturated steam, such as is now practically exclusively used in heatingdrying-cylinders,superheated steam, electricity, or other suitable heating agent can of course after making' the necessary changes be employed in the manner described.

What I claim,.and desire to secure by Letters Patent,is as follows:

1. In a drying apparatus, the combination of a rotatable cylinder, a stationary cylinder concentric therewithandheat-conductingmaterial between the walls of the same, substantially as described.

2. In a drying apparatus, the combination of a rotatable closed cylinder, a stationary closed cylinder concentric therewith and within the same, stationary heating-coils in the space between the walls of the cylinders and liquid heat-conducting material also in said space, substantially as described.

3. In a drying apparatus, the combination of a rotatable closed cylinder, a stationary v closed cylinder concentric therewith and within the same, stationary heating-coils in the space between the walls of the cylinders, and heat-conducting material also in said space, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

, ERNST FUES.

Witnesses:

JEAN GRUND, FRANZ HAssLAcHER. 

